As I write this review, Series 8 has already ended and I've had an opportunity to marathon the entire series from Deep Breath to Death in Heaven to see how everything flows together. Now that I've seen it all a few times, I can safely say that despite having a few weak links here and there, this series has probably been my favourite since Series 1. The evolution of the Doctor and Clara is fascinating to watch and the themes and arcs are so tightly knit that even episodes that appear to be filler (Robot of Sherwood or Time Heist) contribute, mainly by showing how harsh and unfeeling the Twelfth Doctor can be and demonstrating the wonders the Doctor shows Clara to keep her addicted to travelling. I'm even kinda glad we only got twelve episodes this year (with an extended premier and finale) instead of a full thirteen, because I genuinely can't think of a place where a thirteenth episode could be thrown in or what a thirteenth episode would add to the series.
Another thing I love about Series 8 is all of the new blood it brought in to keep Doctor Who fresh and ever-changing, including the superb Jamie Mathieson. Mathieson was given two episodes to write this year, both of which heavily contribute to the overall arc while managing to tell their own individual stories as well, and of the two, Flatline is definitely my favourite.
Where we last left our heroes, Clara was giving in to temptation and continuing to travel with the Doctor despite his dodgy moral code and the fact she had told Danny that she was stopping. In this episode, both the Doctor and Danny quickly discover she's been lying to them but instead of a big fallout the Doctor merely comments that lying is a bad habit and the proper confrontation with Danny is delayed until In the Forest of the Night. I'll admit while I like that it was addressed, I was expecting a lot more repercussions, especially considering Mathieson wrote both the script where she lies and the script where her lie is discovered. Aside from that, this episode does a good job of showing the cause and effect of the Doctor and Clara's behaviour as Clara is forced to step into the Doctor's shoes and experience the difficult choices he normally has to make. We see more than ever here that travelling with the Twelfth Doctor is having a detrimental effect on Clara and she's actually becoming a worse person. This direction Moffat has taken Clara not only makes sense in terms of her specific personality but it's also a refreshing and original take on the Doctor/companion relationship. Although there is still a typical Moffat mystery going on in the form of 'who is Missy?', the main drive of Series 8 is nothing more or less than character development for the two main leads. People complain that all the focus on Clara in Series 8 is detracting, particularly in Peter Capaldi's first series, but in a way we're learning a lot about the Twelfth Doctor by the effect he's having on his companion.
Jenna Coleman makes a very good 'Doctor' and is able to effortlessly take centre stage and command the screen. I love episodes like Turn Left and Blink where other characters have to take on the Doctor's role, and Flatline manages to do it perfectly without making it too much of a gimmick. However, unlike Turn Left and Blink, the Doctor doesn't need to be replaced due to his absence from the story. This isn't exactly a 'Doctor-lite' episode because Peter Capaldi is still present, commenting on the action from inside the TARDIS throughout. The concept of the TARDIS's exterior shrinking in size, while not being a new idea, is extremely well done and Mathieson makes the most out of it, with the stand-out moment being when the Doctor physically moves the TARDIS off of the train tracks. That said, the reason why the TARDIS is on the train tracks to begin with is incredibly contrived. Christopher Fairbank's character randomly grabs it from Clara's bag and throws it away for no reason other than to advance the plot.
The TARDIS Siege Mode is a great idea for a defence mechanism (conveniently giving the Doctor a haircut to last longer in a siege) and a good way to raise the stakes. The ending where the Doctor sends the Boneless back to their own dimension with a press of the sonic screwdriver feels a little anti-climactic but at the very least it's foreshadowed and it makes sense that after cleverly tricking the Boneless by using their own power against, they might as well be defeated at that point instead of having the episode rise to such a high crescendo a second time. It would've been a bit weird if Clara had gone through all that trouble only for the episode to then go on for a bit longer while they actually figure out how to get rid of the monsters.
The Boneless are one of the best original villains we've had for years and it makes me wish more effort was put into creating new monsters instead of churning out new stories for the tired old Daleks and Cybermen every year. The CGI used to bring the Boneless to life is incredible and I'll be very surprised if this episode doesn't win some technical awards. The big reveal that the paintings of the victims in the tunnel are actually the victims themselves squashed into 2D isn't actually that big of a reveal considering I'd already pieced it together based on the pre-titles sequence, but it's still a sinister idea and the effect looked great.
Flatline might be the best episode of Series 8, which is an already amazing run. The script is intelligent, funny, builds on past character development, and sets up the future. Mathieson clearly understands both the characters and the show, and I hope we see more of his work next series.